The disclosure relates generally to liquid guided laser cutting tools, and more particularly, to protective shields for the discharge nozzle of liquid guided laser cutting tools.
Industrial cutting tools combining a high energy laser beam with a focused jet of transparent liquid, such as water, have been in use for a number of years. These systems generally comprise a laser and a beam guide providing the laser beam, an optics module for controllably focusing the laser, a coupling assembly for coupling the laser with a high pressure liquid jet, and a discharge nozzle.
Additional protective features have been added to liquid guided laser cutting tools to protect the integrity of the liquid jet and beam path, as well as to prevent wear or other damage to the nozzle and/or upstream components in the system. These risks are created be several factors, such as feedback from the workpiece created by surface waves or vibration, accidental contact with the workpiece or projections related thereto, suction of particles of ablated material from the workpiece, reflected laser and plasma light, and/or deflected liquid. Certain applications may suggest increased need for protective features.
Some systems employ a nozzle cover or cap that creates a space adjacent the nozzle and serves as a mounting for a thin, replaceable shield. However, additional improvements that enhance reliability of water jet flow, extend the distance between the workpiece and the discharge nozzle (while maintaining effective cutting), last longer, are easier to use, and/or better protect the system are desirable.